Typically, a smart sweeping robot, a smart mopping robot and other kinds of autonomous cleaning devices may perform various types of autonomous cleaning operations, which provide convenience use experience for the user. To clean a large area, the autonomous cleaning device is usually equipped with a built-in power supply, which may enable the autonomous cleaning device to be independent from an external power supply and achieve more liberalize clean operations. Correspondingly, before running out of the built-in power supply, the autonomous cleaning device should be able to automatically recognize the external power supply and accurately go back to the location of the external power supply, so as to be completely relieved from the guard and cooperation operations performed by the user, and achieve a truly automatic clean operation.
The autonomous cleaning device with laser direct structuring (LDS) may take a pattern having regular bright and dark changes as the pattern for recognizing the charging pile. However, the recognition result for the pattern having regular bright and dark changes usually appears to be misjudged, because it's likely to have a pattern similar to the pattern of the charging pile at home (the LDS recognizes brightness and darkness according to the reflected light from an object, and if an object has a alternatively bright and dark stripe thereon, or is composed alternatively by two materials with different reflection intensity, or is shined by sunshine transmitted through a striped fence, the intensity of the reflected light may have a intensity change, which leads to the misjudgment). The cleaning device may mistake for the charging pile and look for the butt joint on furniture or walls with a certain impulsive force repeatedly using its charging electrode made of metal. On the one hand, it's harmful to the furniture or wall, and on the other hand, the robot cannot be charged and continue to work when no person is around it, and may stop in a wrong place when only half of the room is cleaned, which leads to a bad user experience.